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“The annual accidental death toll for handgun- related incidents is slightly under 200” Type of Accident or Manner of Injury1996 Firearm Missile, E9221,134 Handgun187 Shotgun (automatic)93 Hunting rifle50 Other and unspecified firearms missile804 Actual handgun total is some unknown fraction of the 804, likely much more than 200.

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Offenders Sentenced in U.S. District Courts under the U.S. Sentencing Commission guidelines (fiscal year 1999) Primary offense Total cases Race: Other b NumberPercent Total55,3882,1894.0% Sexual abuse % b Includes Native Americans, Alaska Natives, Asians, and Pacific Islanders. 230 is pretty few sexual abuse cases for the whole country, isn’t it? U.S. District Courts – just what courts are those? The explanation: The statistics are limited to federal cases, and the federal government very rarely prosecutes sexual abuse (which is mostly a state law crime) – except on Indian reservations.

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Find four problems with this graphic, which refers to the case that held that use of “under God” in the Pledge of Allegiance is unconstitutional. 1. Did the court of appeals rule that “the Pledge... is unconstitu- tional”? 1. Did the court of appeals rule that “the Pledge... is unconstitu- tional”? It ruled that the inclusion of “under God” in the Pledge is unconstitutional. The remaining 25-odd words were untouched. A picky point, but precision counts. 2. Most of who say ‘Pledge’ is constitutional? 2. Most of who say ‘Pledge’ is constitutional? Seems like it should mean most readers, or most Americans —but fine print says “law students and legal associates.” Not what readers would expect. 3. How were the respondents chosen? 3. How were the respondents chosen? They were self- selected (true of most “online survey[s]”), not randomly chosen. Probably a highly unrepresentative sample even of all “law students and legal associates.” 4. Is the margin of error really ±3%? 4. Is the margin of error really ±3%? With 235 respondents, the margin of error is rougly 100 divided by the square root of 235, or ±6% or so. (Of course, with a self- selected sample the result is meaningless no matter how many people are surveyed.)

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Study: 15% of N.Y. drivers drive drunk at least once a month. Minnesota commentator: 15% of driving-age teenagers drive drunk at least once a month. Study: 15% of N.Y. drivers drive drunk at least once a month. Minnesota commentator: 15% of driving-age teenagers drive drunk at least once a month. 1. Generalizing across places and times—make clear that the numbers refer to the N.Y. study, at the time the study was done. Study: 15% of N.Y. drivers drive drunk at least once a month. Minnesota commentator: 15% of driving-age teenagers drive drunk at least once a month. 1. Generalizing across places and times—make clear that the numbers refer to the N.Y. study, at the time the study was done. 2. Inferring from group’s behavior to a subset’s behavior—do teenage drivers (16-18 or 16-19) behave the same way as 18/19-25-year-olds? Study: 15% of N.Y. drivers drive drunk at least once a month. Minnesota commentator: 15% of driving-age teenagers drive drunk at least once a month. 1. Generalizing across places and times—make clear that the numbers refer to the N.Y. study, at the time the study was done. 2. Inferring from group’s behavior to a subset’s behavior—do teenage drivers (16-18 or 16-19) behave the same way as 18/19-25-year-olds? 3. Misreporting the study—the study focused on fraction of drivers who drive drunk, not on fraction of teenagers who drive drunk.

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[Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [A:] a hand- gun brought into the home for the pur- poses of self- protection is six times more likely to kill a relative or acquaintance than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. [Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [A:] a hand- gun brought into the home for the pur- poses of self- protection is six times more likely to kill a relative or acquaintance than to repel a burglar (i) Small error: “friend” is false synonym for “acquaintance.”

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[Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. [Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. (ii) “Handgun” is a false synonym for “gun.” [Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. (ii) “Handgun” is a false synonym for “gun.” (iii) “Kill a friend or relative” isn’t “fatal firearm accident.” [Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. (ii) “Handgun” is a false synonym for “gun.” (iii) “Kill a friend or relative” isn’t “fatal firearm accident.” (iv) “Repel” isn’t “kill.” [Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. (ii) “Handgun” is a false synonym for “gun.” (iii) “Kill a friend or relative” isn’t “fatal firearm accident.” (iv) “Repel” isn’t “kill.” (v) “Burglar” isn’t “burglar, robber or intruder.” [Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. (ii) “Handgun” is a false synonym for “gun.” (iii) “Kill a friend or relative” isn’t “fatal firearm accident.” (iv) “Repel” isn’t “kill.” (v) “Burglar” isn’t “burglar, robber or intruder.” (vi) Make clear when you’re inferring from a specific time and place to the whole country at a different time.

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[Article:] a handgun is six times more likely to be used to kill a friend or relative than to repel a burglar [B:] During [ in Cuyahoga County], only 23 burglars, robbers or intruders who were not relatives or acquaintances were killed by guns in the hands of persons who were protecting their homes. During this same interval, six times as many fatal firearm accidents occurred in the home. (1) Watch for false synonyms. (2) Watch for inferences from one context to another. (1) Watch for false synonyms. (2) Watch for inferences from one context to another. (3) Look at the original source (B) and not just the intermediate source (A). (1) Watch for false synonyms. (2) Watch for inferences from one context to another. (3) Look at the original source (B) and not just the intermediate source (A). (4) Be careful. Be skeptical.

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[Article:] a person who uses a hand- gun in self- defense is eight times more likely to be killed than one who quietly acquiesces [A:] A survey of Chicago robberies in 1975 revealed that, of those victims taking no resistance measures, the probability of death was 7.67 per 1000 robbery incidents, while the death rate among those taking self-protection measures was per 1000 robbery incidents. The victim was 8 times more likely to be killed when using a self-protective measure than not! [Article:] a person who uses a hand- gun in self- defense is eight times more likely to be killed than one who quietly acquiesces [A:] A survey of Chicago robberies in 1975 revealed that, of those victims taking no resistance measures, the probability of death was 7.67 per 1000 robbery incidents, while the death rate among those taking self-protection measures was per 1000 robbery incidents. The victim was 8 times more likely to be killed when using a self-protective measure than not! (vi½) Silent generalization from Chicago robberies in 1975 to all crimes at any time anywhere. [Article:] a person who uses a hand- gun in self- defense is eight times more likely to be killed than one who quietly acquiesces [A:] A survey of Chicago robberies in 1975 revealed that, of those victims taking no resistance measures, the probability of death was 7.67 per 1000 robbery incidents, while the death rate among those taking self-protection measures was per 1000 robbery incidents. The victim was 8 times more likely to be killed when using a self-protective measure than not! (vi½) Silent generalization from Chicago robberies in 1975 to all crimes at any time anywhere. (vii) Silent inference from “self-protection measures” generally to defensive handgun use.

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Here’s the actual data on deaths associated with various self-protection measures, from source C: Method of Victim Self-ProtectionDeathsTotal Physical force7 (6.1%)114 With Weapon Not a gun05 Handgun06 Verbal Denial of goods2 (4.5%)44 Verbal Shouting2 (3.7%)54 Flight7 (18.9%)37 Verbal or Phys. Resis. & Flight020 Unknown23 (79.3%)29 None7 (0.8%)913 TOTAL48 (3.9%)1222 The “death rate among those taking self-protection measures” (64.29/1000=18/280) says nothing about the death rate among those who use a handgun.

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[Article:] a person who uses a hand- gun in self- defense is eight times more likely to be killed than one who quietly acquiesces [A:] A survey of Chicago robberies in 1975 revealed that, of those victims taking no resistance measures, the probability of death was 7.67 per 1000 robbery incidents, while the death rate among those taking self-protection measures was per 1000 robbery incidents. The victim was 8 times more likely to be killed when using a self-protective measure than not! (1) Watch for false synonyms.(1) Watch for false synonyms. (2) Check original sources. (3) Avoid confusing language—by surrounding the quoted text with discussion of handguns, source A misled the reader into thinking that the quoted text was talking about handguns.